function  loadSelect(positionId,selectedId) {
    //创建提示option,挂在select下
    $("#"+positionId).append($("<option value=''>---请选择---</option>"));
    //ajax请求数据
    $.ajax({
        type: "POST",
        url: "/product/load.do",
        dataType: "json",
        success: function(data){
            $.each(data.brands,function(i,json){
             var $options = $("<option value ='"+json['id']+"'>"+json['name']+"</option>")
                if(json['id']==selectedId){
                    $("#"+positionId).attr("selected","selected");
                }
                $("#"+positionId).append($options);
            })
        }
    });
    /*$.get("/product/load.do",
        function(data){
        alert(data.brands[1].name);
        //遍历对象
          $.each( data,
                 function(i, n){
             alert(n);
                var $option = $("<option value='"+json['id']+"'>"+json['name']+"</option>");
                 if(json['id'] == selectedId){
                     $option.attr("selected","selected");
                 }
              $("#"+positionId).append($option);

             });*!/
        },"json");*/

}